1. Field of the Invention
This invention pertains to antenna systems. In particular, this invention relates to electrically short and coaxially fed antenna systems. More in particular, this invention pertains to an RF balancing system for electrically short and coaxially fed antenna systems.
2. Prior Art
Coaxially fed antenna systems having a half-wave dipole consisting of two pieces of one-quarter wave tubing which are axially aligned and center fed with coaxial cable is known in the prior art. Additionally, coaxial cable extending through one of the two tubular members is also known in the prior art, such prior art antennas utilizing techniques known in the art as Bazooka balun, which is a quarter wavelength piece of tubing passed over the coaxial cable. Such resonates and generally traps out any radiation over the coaxial cable. However, such prior art antenna systems are generally approximately one-half wavelength in overall extended direction. Such prior art antennas are exceedingly lengthy and do not allow for the utility of a shorter extended length antenna system, as is provided in the inventive concept.
Other prior art antenna systems known to applicant include U.S. Pat. Nos. 3,961,332; 3,735,413; 3,789,416; 3,611,397; 3,932,873; 2,344,171; 2,234,234; and, 2,821,709.
In some prior art systems such as that shown in U.S. Pat. No. 3,789,416, the feed line is introduced at right angles to the radiating element axes. This is in contradistinction to the subject invention concept, wherein the RF balancing is provided for coaxially fed antenna systems. Additionally, in prior U.S. Pat. No. 3,611,397, such systems incorporate feed lines at right angles to the antenna axis, which is substantially removed from the coaxial design of the subject invention concept antenna system. In many prior art systems such as that provided in U.S. Pat. No. 3,932,873, there is no RF compensation and further, such provides for antenna dimensions of a quarter-wavelength or greater which would be in contradistinction to the overall concept of the subject antenna system.